Transitions for joining crash impact attenuator systems to fixed structures

ABSTRACT

A transition system for connecting a crash attenuator to a roadside fixed structure, such as a concrete traffic barrier, includes a plate adapted to securely attach to a desired location on the fixed structure, the plate having a flat surface adapted to correspond to a flat surface on the fixed structure, and being reinforced by a plurality of backing ribs for strength.

This application claims the benefit under 35 U.S.C. 119(e) of the filingdate of U.S. Provisional Application Ser. No. 63/135,413, entitledTransitions for Joining Crash Impact Attenuator Systems to FixedStructures, filed on Jan. 8, 2021, which application is expresslyincorporated herein by reference, in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to crash impact attenuators, andmore particularly to motor vehicle and highway barrier crash impactattenuators comprising fixed systems protecting leading edges ofabutments and other fixed roadside hazards. Most particularly, thisinvention is concerned with transition hardware for joining the crashimpact attenuators to the abutments and other fixed roadway hazards.

Vehicular accidents on the highway are a major worldwide problem and areundoubtedly one of the largest causes of economic and human loss andsuffering inflicted on the developed world today. In an effort toalleviate, in particular, the human toll of these tragic accidents,guardrails, crash cushions, truck-mounted crash attenuators, crashbarrels, and the like have been developed to attenuate the impact of thevehicle with a rigid immovable obstacle, such as a bridge abutment.

A crash attenuator of the type described must absorb the vehicle impactenergy without exceeding limits on the vehicle deceleration. Inaddition, it must accommodate both heavy and light weight vehicles. Thelightest vehicle will set the limit on the maximum force produced by theattenuator and the heavy vehicle—which will experience a lowerdeceleration, and thus will determine the total impact deformationrequired. When impacted head-on, crash attenuators/cushions are designedto absorb energy and to gradually slow the vehicle to a controlled stop.The force cannot exceed the light vehicle limit and therefore theinitial force and deceleration is low, limiting the energy absorption.Increasing crash resistance as the vehicle “rides down” from its impactspeed to zero is a vitally important feature of a crash attenuatorsystem which meets rigid governmental safety standards. When impactedobliquely on its side, crash cushions are designed to redirect thevehicle back toward the roadway and to prevent severe impact with therigid point hazard. Typical crash cushions incorporate siderails/panels, intermediate diaphragms, a track to anchor and guide theintermediate diaphragms, and energy absorbers. As crash safety standardshave evolved to higher and higher requirements in order to betterprotect vehicle occupants from injury, it has become clear that newgeneration crash impact attenuators, or crash cushions, are required toperform this function and meet these high standards in innovative,inexpensive, and very simple, but effective, manners.

An important element of an effective crash attenuation system is thetransition, or structural connection, between the crash attenuator andthe rigid structure behind it, and which it is designed to protect. Thepresent invention is directed to a unique and improve transitionstructure for securing a crash attenuator to a fixed structure.

SUMMARY OF THE INVENTION

The present invention provides an improved crash attenuation system,particularly with respect to a significantly improved transition systemfor securing a crash attenuator to a fixed structure which it ispositioned to protect, such as a concrete barrier known in the industryas a “Jersey Barrier”.

More particularly, in one aspect of the invention, there is provided atransition system adapted for securing a roadside safety system to afixed structure, wherein the transition system comprises a plate havinga forward end and a rearward end, as well as a front face and a rearface. The transition system further includes a transition mount adaptedto secure a rearward end of the roadside safety system to the forwardend of the plate, the plate comprising a flat surface which isconfigured to be conformed to a corresponding surface on the fixedstructure.

In exemplary embodiments, the system includes a plurality of aperturesdisposed through the front and rear faces of the plate at its rearwardend, the plurality of apertures being adapted to receive mechanicalfasteners for securing the plate to the corresponding surface on thefixed structure.

Advantageously, the plate includes a taper from a location partiallyalong a length of the plate and extending at an angle rearwardly to therearward end of the plate. This location, in the illustrated embodiment,is about midway along a distance between the forward end of the plateand the rearward end of the plate.

The plate comprises a first width at its forward end and a second widthat its rearward end, the second width being smaller than the firstwidth. The width of the plate narrows gradually from the first width atthe location partially along the length of the plate to the second widthat the rearward end of the plate because of the taper. In theillustrated embodiment, the corresponding surface on the fixed structureis also flat, so that the plate flat surface is adapted to lie in aflush manner on the corresponding flat surface on the fixed structure.

The second width at the rearward end of the plate is adapted tocorrespond in size to a width of the corresponding flat surface on thefixed structure. The taper angle is adapted to the length of thetransition plate and to a size of the corresponding flat surface on thefixed structure. The size of the corresponding flat surface on the fixedstructure is one or more of its length, width, or area.

The transition mount is secured to the forward end of the plate byeither mechanical fasteners or by one or more welds.

In another aspect of the invention, a transition system is providedwhich is adapted for securing a roadside safety system to a fixedstructure, wherein the transition system comprises a plate having aforward end and extending along a length to a rearward end, as well as afront face and a rear face. The system further comprises a transitionmount adapted to secure a rearward end of the roadside safety system tothe forward end of the plate. A plurality of reinforcement ribs aredisposed in spaced relation to one another on the rear face of theplate.

Each one of the plurality of reinforcement ribs is disposed along thelength of the plate, and each of the plurality of reinforcement ribs hasits own length. The lengths of at least two of the plurality ofreinforcement ribs are different from one another, permitting the ribsto be customized to the length and configuration of the plate,particularly taking the taper of the plate into account. Advantageously,each of the plurality of reinforcement ribs is comprised of a C-channelconstruction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an exemplary embodiment of a crashattenuator and transition structure constructed in accordance with theprinciples of the present invention, taken from a forward perspective,looking rearward;

FIG. 2 is an isometric view similar to FIG. 1, taken from a rearwardperspective, looking forward;

FIG. 3 is an isometric view of an exemplary embodiment of the transitionstructure of the present invention;

FIG. 4 is a plan view of the transition structure of FIG. 3;

FIG. 5 is a top view of the transition structure of FIGS. 3 and 4; and

FIG. 6 is a plan view of the rear or back face of the transitionstructure of FIGS. 3-5.

DETAILED DESCRIPTION OF THE INVENTION

Referring now more particularly to the drawings, there is shown in FIGS.1 and 2 a vehicular crash attenuator 10, which is secured to a fixedabutment or structure 20 by means of a transition plate 30. Thetransition plate 30 is shown in greater detail in FIGS. 3-6.

The vehicular crash attenuator 10 may be of any known type in theindustry, typically constructed with a nosepiece 12 at a front endthereof, designed to absorb the first impact from an errant vehicle, anda plurality of compressible sections or stages 14 (FIG. 2). Theillustrated example is the DELTA CRASH CUSHION® system, sold by theapplicant for the present application, TrafFix Devices, Inc., of SanClemente, Calif., and herein expressly incorporated by reference, butother available crash attenuation systems, available from competitors inthe roadside safety marketplace, may also be used.

The transition plate 30 is constructed to be conformed to or compatiblewith the surface of the fixed structure to which it is to be attached,so that the plate lies in a flush manner on that surface when attached.Thus, in the illustrated embodiment, the transition place 30 issubstantially flat in configuration, as opposed to prior art transitionplates which are typically of a thrie-beam construction. The term“substantially flat” means that it is designed to be flat, and ismanufactured to that design, within certain reasonable tolerances.Henceforth, and throughout the claims, the term “flat” will be used, butit is to be understood to mean “substantially flat” to allow for thetolerances typical in all manufacturing operations. The transitionplate, as shown, is designed with a taper and shape to mimic theconcrete barrier, in this case a barrier commonly identified in theindustry as a “Jersey Barrier” to which it is adapted to be attached.However, the type of fixed structure is not important to theinvention—any such structure or object having an available flat surfaceto which the rearward end of the plate can be attached is potentiallyusable with the inventive transition system.

More particularly, the plate 30 includes a taper 32 from a location 34partially (about midway) along a length of the plate 30 and extendingrearwardly to a rearward end 36 of the plate 30. Thus, the plate 30comprises a first width at its forward end, and a second smaller widthat its rearward end 36, the width of the plate narrowing gradually fromthe first width to the second smaller width along the taper 32.

Bolt holes 40 are disposed in the rearward end 36 of the plate 30 forsecuring the plate 30 to the fixed structure 20, extending through afront face 41 a of the plate and a rear face 41 b of the plate. Notethat the taper 32 may be adapted to narrow the plate 30 so that at itsrearward end 36, it is sized so that its width corresponds to the widthof an available flat surface 42 on the fixed structure 20, and therearward end 36 of the plate 30 may thus be readily secured to theavailable flat surface 42 using bolts disposed through the bolt holes40. Thus, the angle of the taper is adaptable to the length of thetransition plate and the size (length, width, and/or area) of theavailable flat surface 42 on the structure 20, so that no matter thetype of structure to which the transition is to be secured, thatsecurement should be easily attained.

Transition mount 44 is adapted to secure the rearward end of the crashattenuator 10 to the transition plate 30. Fastening of the transitionmount 44 may be attained by using mechanical fasteners, but may also beby welding.

Shims 46, illustrated as being of wood, may be inserted between theplate 30 and the fixed structure 20 in locations where there is a gapbetween the plate 30 and the structure 20, to fixedly secure the plateto the structure between the transition mount 44 and the fasteners atthe rearward end 36 of the plate.

A plurality of ribs 48 may be advantageously secured to the rear face 41b of the transition plate 30 (FIG. 6) to reinforce the plate. Asillustrated, the plurality of ribs are of differing lengths, extendingalong the length of the plate and spaced vertically from one another, inorder to be adapted to the configuration and taper of the plate.Although the structural ribs 48 may be formed of most any known shape,such as commonly available box tubes, they are advantageously formedusing a C-channel structure, with the open side of the C-channel facingthe rear plate face 41 b. This arrangement is advantageous because itavoids a double thickness of material, thus maximizing costeffectiveness without reducing the strength of the plate.

In one exemplary embodiment, for illustrative purposes only, the plate30 is 3/16 inch plate, with a galvanized finish. The rearward end(second) width is 15.3 in., and the front end (first) width is 24.0inches.

The innovative transition plate of the present invention has been foundto result in successful crash testing under current federal MASHstandards. In particular, it has been found to minimize snagging,minimize vehicle floor board deformation, and to maximize re-directionof the impacting vehicle.

What is claimed is:
 1. A transition system adapted for securing aroadside safety system to a fixed structure, the transition systemcomprising: a plate having a forward end and a rearward end, as well asa front face and a rear face; and a transition mount adapted to secure arearward end of the roadside safety system to the forward end of theplate, the plate comprising a flat surface which is configured to beconformed to a corresponding surface on the fixed structure.
 2. Thetransition system as recited in claim 1, and further comprising aplurality of apertures disposed through the front and rear faces of theplate at its rearward end, the plurality of apertures being adapted toreceive mechanical fasteners for securing the plate to the correspondingsurface on the fixed structure.
 3. The transition system as recited inclaim 1, wherein the plate includes a taper from a location partiallyalong a length of the plate and extending at an angle rearwardly to therearward end of the plate.
 4. The transition system as recited in claim3, wherein the location partially along the length of the plate is aboutmidway along a distance between the forward end of the plate and therearward end of the plate.
 5. The transition system as recited in claim3, wherein the plate comprises a first width at its forward end and asecond width at its rearward end, the second width being smaller thanthe first width.
 6. The transition system as recited in claim 5, whereinthe width of the plate narrows gradually from the first width at thelocation partially along the length of the plate to the second width atthe rearward end of the plate because of the taper.
 7. The transitionsystem as recited in claim 6, wherein the corresponding surface on thefixed structure is also flat, so that the plate flat surface is adaptedto lie in a flush manner on the corresponding flat surface on the fixedstructure.
 8. The transition system as recited in claim 7, wherein thesecond width at the rearward end of the plate is adapted to correspondin size to a width of the corresponding flat surface on the fixedstructure.
 9. The transition system as recited in claim 8, wherein thetaper angle is adapted to the length of the transition plate and to asize of the corresponding flat surface on the fixed structure.
 10. Thetransition system as recited in claim 9, wherein the size of thecorresponding flat surface on the fixed structure is one or more of itslength, width, or area.
 11. The transition system as recited in claim 1,wherein the transition mount is secured to the forward end of the plateby either mechanical fasteners or by one or more welds.
 12. Thetransition system as recited in claim 1, and further comprising aplurality of reinforcement ribs disposed in spaced relation to oneanother on the rear face of the plate.
 13. A transition system adaptedfor securing a roadside safety system to a fixed structure, thetransition system comprising: a plate having a forward end and extendingalong a length to a rearward end, as well as a front face and a rearface; a transition mount adapted to secure a rearward end of theroadside safety system to the forward end of the plate; and a pluralityof reinforcement ribs disposed in spaced relation to one another on therear face of the plate.
 14. The transition system as recited in claim13, wherein each of the plurality of reinforcement ribs is disposedalong the length of the plate, each of the plurality of reinforcementribs having a length.
 15. The transition system as recited in claim 14,wherein the lengths of at least two of the plurality of reinforcementribs are different from one another.